The eastern region of the former princely state of Kashmir has also been involved in a boundary dispute. In the late 19th- and early 20th centuries, although some boundary agreements were signed between Great Britain, Afghanistan and Russia over the northern borders of Kashmir, China never accepted these agreements, and the official Chinese position did not change with the communist revolution in 1949. By the mid-1950s the Chinese army had entered the north-east portion of Ladakh.
"By 1956–57 they had completed a military road through the Aksai Chin area to provide better communication between Xinjiang and western Tibet. India's belated discovery of this road led to border clashes between the two countries that culminated in the Sino-Indian war of October 1962."
The region is divided among three countries in a territorial dispute: Pakistan controls the northwest portion (Northern Areas and Azad Kashmir), India controls the central and southern portion (Jammu and Kashmir) and Ladakh, and China controls the northeastern portion (Aksai Chin and the Trans-Karakoram Tract). India controls the majority of the Siachen Glacier area including the Saltoro Ridge passes, whereas Pakistan controls the lower territory just southwest of the Saltoro Ridge. India controls 101,338 km2 (39,127 sq mi) of the disputed territory, Pakistan 85,846 km2 (33,145 sq mi) and China, the remaining 37,555 km2 (14,500 sq mi).
Jammu and Pakistan administered Kashmir lie outside Pir Panjal range, and are under Indian and Pakistani control respectively. These are populous regions. The main cities are Mirpur, Dadayal, Kotli, Bhimber Jammu, Muzaffarabad and Rawalakot.
The Gilgit–Baltistan, formerly called Northern Areas, are a group of territories in the extreme north, bordered by the Karakoram, the western Himalayas, the Pamir, and the Hindu Kush ranges. With its administrative center at the town of Gilgit, the Northern Areas cover an area of 72,971 km² (28,174 mi²) and have an estimated population approaching 1,000,000. The other main city is Skardu.
Ladakh is a region in the east, between the Kunlun mountain range in the north and the main Great Himalayas to the south. Main cities are Leh and Kargil. It is under Indian administration and is part of the state of Jammu and Kashmir. It is one of the most sparsely populated regions in the area and is mainly inhabited by people of Indo-Aryan and Tibetan descent.
Aksai Chin is a vast high-altitude desert of salt that reaches altitudes up to 5,000 metres (16,000 ft). Geographically part of the Tibetan Plateau, Aksai Chin is referred to as the Soda Plain. The region is almost uninhabited, and has no permanent settlements.
Though these regions are in practice administered by their respective claimants, neither India nor Pakistan has formally recognised the accession of the areas claimed by the other. India claims those areas, including the area "ceded" to China by Pakistan in the Trans-Karakoram Tract in 1963, are a part of its territory, while Pakistan claims the entire region excluding Aksai Chin and Trans-Karakoram Tract. The two countries have fought several declared wars over the territory. The Indo-Pakistani War of 1947 established the rough boundaries of today, with Pakistan holding roughly one-third of Kashmir, and India one-half, with a dividing line of control established by the United Nations. The Indo-Pakistani War of 1965 resulted in a stalemate and a UN-negotiated ceasefire.